Glaucoma and Screen Time: Is There a Link?

With the average adult now spending upwards of seven hours a day looking at screens, it is no surprise that people are asking whether all that digital device use could be harming their eyes in ways beyond simple eye strain. One question that comes up frequently is whether screen time can cause or contribute to glaucoma. The answer, based on current evidence, is nuanced, and worth understanding.

The Short Answer: No Direct Causal Link

As of today, there is no strong scientific evidence establishing a direct causal relationship between screen time and glaucoma. Staring at your phone, computer, or tablet does not, in and of itself, damage your optic nerve or cause glaucoma to develop.

However, that is not quite the end of the story. The relationship between screen time and eye health is more complex than a simple yes or no, and there are indirect pathways that are worth paying attention to, particularly the connection between screen time, myopia and glaucoma risk.

Screen Time and Myopia: A Well-Established Connection

What we do know with increasing certainty is that excessive screen time, particularly in childhood and adolescence, is a significant contributing factor to the development and progression of myopia (short-sightedness). The global prevalence of myopia has been rising sharply, and researchers consistently point to increased near work and reduced time spent outdoors as key drivers.

Studies across East Asia, Europe and Australia have shown that children who spend more time on near-work activities (reading, devices, homework) and less time outdoors are more likely to develop myopia. The relationship is strong enough that public health campaigns in countries like Singapore and Taiwan actively encourage outdoor time as a preventive measure.

The Myopia-Glaucoma Connection

This is where the indirect link becomes clinically relevant. Myopia, especially moderate to high myopia, is a well-recognised risk factor for glaucoma. People with myopia are estimated to have a two to three times higher risk of developing open-angle glaucoma compared to those without myopia, and the risk increases with the degree of short-sightedness.

Why does myopia increase glaucoma risk? Several structural factors are involved:

• Longer eyeball: Myopic eyes are physically longer than normal eyes. This elongation places mechanical stress on the structures at the back of the eye, including the optic nerve head and the surrounding tissues.
• Thinner retinal nerve fibre layer: Research has shown that myopic eyes tend to have a thinner retinal nerve fibre layer (RNFL) to begin with. Since glaucoma damages this very layer, starting with less "reserve" means functional vision loss may occur sooner.
• Structural changes to the optic nerve: The optic nerve head in myopic eyes can appear tilted, rotated, or have atypical configurations that make glaucoma harder to detect and may also make the nerve more susceptible to pressure-related damage.
• Lamina cribrosa changes: The lamina cribrosa, the sieve-like structure through which nerve fibres pass as they exit the eye, may be thinner and more deformable in myopic eyes, potentially increasing vulnerability to pressure fluctuations.

So while screen time does not directly cause glaucoma, it contributes to myopia, and myopia is a genuine risk factor for glaucoma. The chain of association is real, even if it is indirect.

Can Screen Time Raise Eye Pressure?

Some studies have investigated whether prolonged near work or device use can temporarily elevate intraocular pressure (IOP). The findings have been mixed, but a few small studies have reported modest, transient increases in IOP during sustained near-focus tasks. The clinical significance of these temporary elevations is not yet clear, and they do not appear to be large enough to independently cause glaucoma in healthy eyes.

That said, for individuals who already have glaucoma or are at higher risk, any factor that influences IOP, even temporarily, may be worth discussing with their eye care professional. Head position during device use (for example, lying face down while reading a tablet) has also been shown to increase IOP in some studies, though again the long-term implications are uncertain.

What We Know and What We Do Not

The evidence currently tells us the following:

• Screen time does not directly cause glaucoma based on available research.
• Excessive screen time contributes to myopia development, particularly in younger populations.
• Myopia is a well-established risk factor for glaucoma.
• Some studies suggest temporary IOP elevation during prolonged near work, but the clinical impact is unclear.
• More long-term research is needed to fully understand the downstream effects of the current generation's screen habits on eye disease later in life.

What You Can Do

While you do not need to panic about your screen habits causing glaucoma, a balanced approach to eye health is sensible. Encourage children and teenagers to spend time outdoors, as at least one to two hours per day has been shown to be protective against myopia development. Follow the 20-20-20 rule: every 20 minutes, look at something 20 feet away for at least 20 seconds. And most importantly, ensure you are having regular comprehensive eye exams, especially if you have myopia or other risk factors for glaucoma.

Want to learn more about your personal risk factors? G-Screen's free educational risk check takes around 6 minutes and helps you understand whether a comprehensive eye exam might be a good next step.